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        var time = prompt('请输入时间点：');
        if (time == 12) {
            alert('中午好');
        } else if (time  == 18) {
            alert('傍晚好');
        } else if (time == '23点') {
            alert('深夜好');
        } else {
            alert('没有这个时间点哟！')
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